1. Field of the Invention
This invention is concerned with a methodology for transforming editable documents cast in a first form by and for use in an interactive text processing system into a second editable form for use in and by another text processing system, either of the interactive or batch type, in which said first form is otherwise incompatible. More particularly, this invention is directed to achieving the requisite transformation between dissimilar forms of an editable document by utilizing methodology that effects the transform of an input item from the interactive source form to an explicit set of output items for the editable target document form based on suitably selected state variables representing conditions of the source document form at the point of transformation.
2. Description of the Prior Art
Several different forms are known and commonly used for representing editable or revisable documents in information handling systems. Some examples are OIIA L3 used by Displaywriter and 5520 Systems, a form often called "Two-Baker" used by 3790 and DOSF/DPCX/8100, and the DCF input form used by Document Composition Facility and Professional Office System. Displaywriter is a word processor, capable of and primarily intended for stand-alone operation, manufactured and sold by International Business Machines Corporation (IBM Corporation). It is a type of text processor commonly known as a "what you see is what you get" or interactive system. The 5520 is a shared logic, multi-station text processing and office communication system that is also sold by IBM Corporation. The 3790, classifiable as a minicomputer, is an intelligent text processing system. The 8100, which is also classifiable as a minicomputer, is adapted using DOSF, a text processing package, and DPCX, a special operating system, as a text processing system. Both the 3790 and 8100 are manufactured and sold by IBM Corporation. Document Composition Facility (DCF) or SCRIPT/VS is a text processing program product sold by IBM Corporation. The Professional Office System or PROFS is a menu driven program product sold by IBM Corporation that is designed and particularly suitable for handling and managing a wide spectrum of office related tasks. It includes text processing capabilities that utilize the DCF form of editable text representation. In this type of text processing system, the operator imbeds textual matter in the document that is subsequently interpreted as one or more formatting commands and is retained in the editable document form as textual matter. This document form, when subsequently interpreted, is formatted as a whole document or batch processed.
These are several of the available text processing systems from IBM Corporation that can be employed to create, manipulate and format editable documents. There are also many other fine text processing systems and software support therefor available from other suppliers. Due to the overwhelming number of text processing systems now available, it is not uncommon to have a diverse mix of different text processors at any particular installation. However, due to incompatibility in and between the editable documents produced by the various text processing systems, it has been extremely difficult to provide a document form transformation capability for different people who need to cooperate in creating and editing a given document. Further, that need contemplates that each party involved in editing the document be provided with several opportunities to do so. This need cannot be efficiently or effectively supported in an operating environment that uses text processors having impenetrable system boundaries.
There are obvious and important benefits to be derived from transforming documents generated in a known form by a first text processing system, into another form that is useable and fully editable on a different text processing system. Without such transformation capability, documents prepared on any one of the known systems are meaningless to and unmodifiable by users of other systems. However, the provision of a transformation capability is not a straightforward or simple endeavor. It will be understood by those having skill in this art that the required transformation facility necessary to permit a first form document to be converted into a second form document that can be edited on a different and otherwise incompatible text processing system involves more than just a mere one-for-one replacement or substitution formula.
One known prior art example of a transformation methodology is provided by the Document Interchange Facility or DIF. This IBM Corporation program product is provided to convert "Two-Baker" form editable files into DCF form files by using uniquely defined SCRIPT macros. These macros essentially invoke a block of information for each of the "Two-Baker" commands encountered, but the substituted material is not an equivalent DCF command. While it does permit a final formatted version of the original "Two-Baker" document to be produced by a DCF based text processing system using the translated file containing these macros, this DIF converted data stream cannot be easily edited or effectively manipulated because that data stream is atypical, it is not a normal DCF file. This approach permits the formatting of a document cast in a first editable form in a text processor designed for documents of a second form, but does not allow for editing of the "transformed" document at any point prior thereto.